Book digitized by Google and uploaded to the Internet Archive by user tpb.
Publisher Little, Brown, and company
Possible copyright status NOT_IN_COPYRIGHT
Digitizing sponsor Google
Book from the collections of unknown library
Notes "Part of the first chapter has been published already, and under its present title in 'The medical record,' New York ... Part of the substance of the other chapters appeared as a serial in 'The Scientific American supplement' in the spring of 1916."--Pref.